i have an external USB HDD with 2 partitions.
I'm playing my rock band 3 saved in the USB HDD WBFS partition.
The other partition is a FAT32 partition

I use Configurable USB Loader release v70 to access the HDD and I can play Rock band 3 with all instruments. No problem

But I have two issues:

1. When Im playing, and have to stop for a few minutes, the controllers lose connection and I have to reset the game. Can this be fixed?
2. How do I save the downloaded songs to the usb fat32 partition?

you need to update. either do it with Modmii or NUS downloader and simulate and update for your region. i recommend updating all the IOS files but only going to system menu 4.1. Just make sure you have the corresponding IOS for the system menu (Modmii will ensure this). you also need to remove the stubs in 222/223 so you can install Hermes IOS there.